#include<stdio.h>
int main()
{
	int i = 0;
	scanf_s("%d", &i);
	switch (i)
	{
	case 1:
	case 2:
		putchar('i');
	case 3:
		printf("%d\n", i);
		break;
	default:
		printf("OK!\n");

	}
	return 0;
}